In the past, people use incandescent lamps for night or indoor illumination because the incandescent lamps can provide some advantages including simple installation. However, since the incandescent lamps also have some disadvantages including high power consumption, short lamp life (average life of only about 1,000 hours) etc., more and more users change to use energy-saving fluorescent lamps about ten years ago based on demands of environmental protection and energy saving. The so-called “fluorescent lamp” is an integral illumination apparatus constructed by a fluorescent bulb and a ballast, with an average life up to 6,000 hours. The size of the fluorescent lamp is similar to that of the incandescent lamp, wherein a holder interface (i.e. an electrode cap or head) of the fluorescent lamp is also the same as that of the incandescent lamp, so that the fluorescent lamp can be directly used to replace the incandescent lamp. In addition, the luminous efficiency of the fluorescent lamp is considerably greater than that of the incandescent lamp, and the power consumption of the fluorescent lamp is considerably less than that of the incandescent lamp under identical illumination conditions. Thus, generally, the fluorescent lamp is also called an energy-saving lamp.
In addition to the foregoing incandescent lamp and fluorescent lamp, with the development of light emitting diodes (LEDs) technologies, many lamp manufacturers start to develop and manufacture various different types of illumination apparatuses using LEDs as the main light sources. Because the LED lamps can provide some advantages including energy saving, long lamp life (about 40,000 hours), and toxic substances (such as mercury, Hg) free, while the light spectrum generated by the light source of the LED lamps almost doesn't include ultraviolet or infrared, wherein the light emitted by the LEDs almost has no problems of waste heat or irradiation. Besides, the cost of the LEDs is lowered day by day, so that more and more users pay attention to various possible applications of the LED lamps.
Recently, Sharp Corporation in Japan developed a new type of LED lamps which has an inner space for receiving a power printed circuit board (PCB) and being filled with a filler material used to increase the efficiency of thermal conduction and cooling of the power PCB. However, because the weight of the filler material is heavy and the cost of the filler material is relatively high, the type of LED lamp can not be widely used in the market of the LED lamps. Then, Toshiba Corporation developed another series of LED lamps called E-CORE to improve the foregoing disadvantages for the purpose of lowering the cost and sell price thereof to increase the market share. However, there are still some problems existing in the installation of the type of LED lamps in the production line. The structure of the type of LED lamps will be described below with reference to FIG. 1.
An LED lamp as shown in FIG. 1 comprises a heat dissipation housing 10, an electrode cap 11, an insulation resin housing 12, a power printed circuit board (PCB) 13, a light emitting module 14 and a lamp shade 15, wherein the heat dissipation housing 10 is made of aluminum alloy and generally formed by metal casting to integrate into one piece. The heat dissipation housing 10 is extended outward to form a plurality of cooling fins 100, while a lower side of the heat dissipation housing 10 is formed with a receiving hole (not shown) therein for receiving the insulation resin housing 12. In addition, an upper side of the heat dissipation housing 10 is formed with a first wire hole 101, while an upper side of the insulation resin housing 12 is formed with a second wire hole 120 and a thread hole 121, wherein the insulation resin housing 12 is screw-connected into the receiving hole of the heat dissipation housing 10 by a screw 16. The power PCB 13 is disposed in the insulation resin housing 12 to prevent wires or electronic components on the power PCB 13 from directly contacting the heat dissipation housing 10 according to the good insulation property of the insulation resin housing 12, so as to protect the power PCB 13 from possible short-circuit problem. Furthermore, the light emitting module 14 has an installation base plate 141 and a plurality of LEDs 142, wherein one side of the installation base plate 141 is provided with conductive circuits (unlabeled) which are connected to and installed with the LEDs 142, respectively. The installation base plate 141 is also formed with a third wire hole 143, wherein two wires 130 of the power PCB 13 can pass through the second, first and third wire holes 120, 101, 143 in turn to be electrically connected to the conductive circuits on the installation base plate 141 of the light emitting module 14. Moreover, the other two wires 131 of the power PCB 13 can be electrically connected to the electrode cap 11 which is screw-connected to a lower end of the insulation resin housing 12. The light emitting module 14 can obtain an external power through the power PCB 13 and the electrode cap 11 and then supply the power to the LEDs 142, so that the LEDs can emit the light.
Besides, as shown in FIG. 1, the other side of the installation base plate 141 is installed on the upper side of the heat dissipation housing 10, so that waste heat generated by the LEDs 142 can be transferred to the heat dissipation housing 10 through the other side of the installation base plate 141 and dissipated to the ambient atmosphere through the heat dissipation housing 10. As a result, the operational temperature of the LEDs 142 can be efficiently lowered down, so that the LEDs can emit ideal color light. In addition, the shape of the lamp shade 15 is approximately a semi-sphere shape, and the lamp shade 15 is covered on the heat dissipation housing 10. An opening edge (unlabeled) of the lamp shade 15 is attached to an edge of the upper side of the heat dissipation housing 10 by adhesive. The light emitted by the LEDs 142 can pass through the lamp shade 15 to illuminate an external environment of the LED lamp.
Generally, when a lamp manufacturer installs the foregoing LED lamp in a production line, the insulation resin housing 12 is firstly installed into the heat dissipation housing 10 from the lower side of the heat dissipation housing 10. Then, the screw 16 is screw-connected into the thread hole 121 of the insulation resin housing 12, in order to position the insulation resin housing 12 into the heat dissipation housing 10. After this, the power PCB 13 is installed and positioned in the insulation resin housing 12, and then electrically connected to the electrode cap 11 through the wires 131. However, an operator must manually install the insulation resin housing 12 into the heat dissipation housing 10 and then screw-connect the insulation resin housing 12 to a predetermined position of the heat dissipation housing 10 through the screw 16 in turn. Thus, the manual installation needs too much man power and substantially increase the operational time of the production line, so as to cause negative effect to the production efficiency of the lamp manufacturer and increase the error installation risk of the operator. For example, the insulation resin housing 12 or the electrode cap 11 may not be positioned to the predetermined positions of the heat dissipation housing 10, so as to lower the product yield of the LED lamp. Moreover, when the operator installs the insulation resin housing 12 into the heat dissipation housing 10, an offset of the positioning precision between the insulation resin housing 12 and the heat dissipation housing 10 may be easily occurred to cause too low product yield of the LED lamp.
As a result, it is an important issue for the present invention to think how to improve the structure of the traditional LED lamp, in order to simplify the component processing and the installation procedure thereof for the purpose of substantially enhancing the production efficiency and the product yield of the LED lamp.
It is therefore tried by the inventor to develop an LED lamp to simplify the component processing and the installation procedure thereof, so as to further enhance the production efficiency and the product yield of the LED lamp.